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Rivet 4.0.0
Rivet::Thrust Class Referenceabstract

Get the e+ e- thrust basis and the thrust, thrust major and thrust minor scalars. More...

#include <Thrust.hh>

Inheritance diagram for Rivet::Thrust:
Rivet::AxesDefinition Rivet::Projection Rivet::ProjectionApplier

Public Member Functions

 Thrust ()
 Constructor.
 
 Thrust (const FinalState &fsp)
 
 RIVET_DEFAULT_PROJ_CLONE (Thrust)
 Clone on the heap.
 
virtual unique_ptr< Projectionclone () const =0
 Clone on the heap.
 
virtual std::string name () const
 Get the name of the projection.
 
bool valid () const
 Get the state of the projetion.
 
bool failed () const
 Get the state of the projetion.
 
void markAsOwned () const
 Mark this object as owned by a proj-handler.
 
double thrust () const
 
double thrustMajor () const
 The thrust major scalar, \( M \), (thrust along thrust major axis).
 
double thrustMinor () const
 The thrust minor scalar, \( m \), (thrust along thrust minor axis).
 
double oblateness () const
 The oblateness, \( O = M - m \) .
 
const Vector3thrustAxis () const
 
const Vector3thrustMajorAxis () const
 The thrust major axis (axis of max thrust perpendicular to thrust axis).
 
const Vector3thrustMinorAxis () const
 The thrust minor axis (axis perpendicular to thrust and thrust major).
 
const Vector3axis1 () const
 AxesDefinition axis accessors.
 
const Vector3axis2 () const
 The 2nd most significant ("major") axis.
 
const Vector3axis3 () const
 The least significant ("minor") axis.
 
Direct methods

Ways to do the calculation directly, without engaging the caching system

void calc (const FinalState &fs)
 Manually calculate the thrust, without engaging the caching system.
 
void calc (const vector< Particle > &fsparticles)
 Manually calculate the thrust, without engaging the caching system.
 
void calc (const vector< FourMomentum > &fsmomenta)
 Manually calculate the thrust, without engaging the caching system.
 
void calc (const vector< Vector3 > &threeMomenta)
 Manually calculate the thrust, without engaging the caching system.
 
Projection operation and comparison
bool before (const Projection &p) const
 
Projection "getting" functions
std::set< ConstProjectionPtr > getProjections () const
 Get the contained projections, including recursion.
 
std::set< ConstProjectionPtr > getImmediateChildProjections () const
 Get the contained projections, excluding recursion.
 
bool hasProjection (const std::string &name) const
 Does this applier have a projection registered under the name name?
 
template<typename PROJ >
const PROJ & getProjection (const std::string &name) const
 
const ProjectiongetProjection (const std::string &name) const
 
template<typename PROJ >
const PROJ & get (const std::string &name) const
 
template<typename PROJ >
const PROJ & getProjectionFromDeclQueue (const std::string name) const
 
Projection applying functions
template<typename PROJ = Projection>
std::enable_if_t< std::is_base_of< Projection, PROJ >::value, const PROJ & > apply (const Event &evt, const Projection &proj) const
 Apply the supplied projection on event evt.
 
template<typename PROJ = Projection>
std::enable_if_t< std::is_base_of< Projection, PROJ >::value, const PROJ & > apply (const Event &evt, const PROJ &proj) const
 Apply the supplied projection on event evt (user-facing alias).
 
template<typename PROJ = Projection>
std::enable_if_t< std::is_base_of< Projection, PROJ >::value, const PROJ & > apply (const Event &evt, const std::string &name) const
 Apply the supplied projection on event evt (user-facing alias).
 
template<typename PROJ = Projection>
std::enable_if_t< std::is_base_of< Projection, PROJ >::value, const PROJ & > apply (const std::string &name, const Event &evt) const
 Apply the supplied projection on event evt (convenience arg-reordering alias).
 

Protected Member Functions

void project (const Event &e)
 Perform the projection on the Event.
 
CmpState compare (const Projection &p) const
 Compare projections.
 
LoggetLog () const
 Get a Log object based on the getName() property of the calling projection object.
 
void setName (const std::string &name)
 Used by derived classes to set their name.
 
void fail ()
 Set the projection in an unvalid state.
 
Cmp< ProjectionmkNamedPCmp (const Projection &otherparent, const std::string &pname) const
 
Cmp< ProjectionmkPCmp (const Projection &otherparent, const std::string &pname) const
 
ProjectionHandlergetProjHandler () const
 Get a reference to the ProjectionHandler for this thread.
 
void setProjectionHandler (ProjectionHandler &projectionHandler) const
 
Projection registration functions
template<typename PROJ >
const PROJ & declare (const PROJ &proj, const std::string &name) const
 Register a contained projection (user-facing version)
 
template<typename PROJ >
const PROJ & declare (const std::string &name, const PROJ &proj) const
 Register a contained projection (user-facing, arg-reordered version)
 

Detailed Description

Get the e+ e- thrust basis and the thrust, thrust major and thrust minor scalars.

Author
Andy Buckley

The scalar (maximum) thrust is defined as

\[ T = \mathrm{max}_{\vec{n}} \frac{\sum_i \left|\vec{p}_i \cdot \vec{n} \right|}{\sum_i |\vec{p}_i|} \]

, with the direction of the unit vector \( \vec{n} \) which maximises \( T \) being identified as the thrust axis. The unit vector which maximises the thrust scalar in the plane perpendicular to \( \vec{n} \) is the "thrust major" direction, and the vector perpendicular to both the thrust and thrust major directions is the thrust minor. Both the major and minor directions have associated thrust scalars.

Thrust calculations have particularly simple forms for less than 4 particles, and in those cases this projection is computationally minimal. For 4 or more particles, a more general calculation must be carried out, based on the Brandt/Dahmen method from Z. Phys. C1 (1978). While a polynomial improvement on the exponential scaling of the naive method, this algorithm scales asymptotically as \( \mathcal{O}\left( n^3 \right) \). Be aware that the thrust may easily be the most computationally demanding projection in Rivet for large events!

The Rivet implementation of thrust is based heavily on Stefan Gieseke's Herwig++ re-coding of the 'tasso' code from HERWIG.

NB. special case with >= 4 coplanar particles will still fail. NB. Thrust assumes all momenta are in the CoM system: no explicit boost is performed. This can be dealt with by appropriate choice of the supplied FinalState.

Member Function Documentation

◆ apply()

template<typename PROJ = Projection>
std::enable_if_t< std::is_base_of< Projection, PROJ >::value, const PROJ & > Rivet::ProjectionApplier::apply ( const Event evt,
const Projection proj 
) const
inlineinherited

Apply the supplied projection on event evt.

Apply the supplied projection on event evt (user-facing alias).

Referenced by Rivet::ALICE::V0Trigger< MODE >::project().

◆ axis1()

const Vector3 & Rivet::Thrust::axis1 ( ) const
inlinevirtual

AxesDefinition axis accessors.

Implements Rivet::AxesDefinition.

References thrustAxis().

◆ axis2()

const Vector3 & Rivet::Thrust::axis2 ( ) const
inlinevirtual

The 2nd most significant ("major") axis.

Implements Rivet::AxesDefinition.

References thrustMajorAxis().

◆ axis3()

const Vector3 & Rivet::Thrust::axis3 ( ) const
inlinevirtual

The least significant ("minor") axis.

Implements Rivet::AxesDefinition.

References thrustMinorAxis().

◆ before()

bool Rivet::Projection::before ( const Projection p) const
inherited

Determine whether this object should be ordered before the object p given as argument. If p is of a different class than this, the before() function of the corresponding type_info objects is used. Otherwise, if the objects are of the same class, the virtual compare(const Projection &) will be returned.

◆ clone()

virtual unique_ptr< Projection > Rivet::AxesDefinition::clone ( ) const
pure virtualinherited

Clone on the heap.

Implements Rivet::Projection.

◆ compare()

CmpState Rivet::Thrust::compare ( const Projection p) const
inlineprotectedvirtual

Compare projections.

Implements Rivet::Projection.

References Rivet::Projection::mkNamedPCmp().

◆ declare() [1/2]

template<typename PROJ >
const PROJ & Rivet::ProjectionApplier::declare ( const PROJ &  proj,
const std::string &  name 
) const
inlineprotectedinherited

Register a contained projection (user-facing version)

Todo:
Add SFINAE to require that PROJ inherit from Projection

Referenced by Rivet::CentralEtHCM::CentralEtHCM(), Rivet::CentralityEstimator::CentralityEstimator(), Rivet::ChargedLeptons::ChargedLeptons(), Rivet::ALICE::CLMultiplicity< INNER >::CLMultiplicity(), Rivet::DISDiffHadron::DISDiffHadron(), Rivet::DISFinalState::DISFinalState(), Rivet::DISKinematics::DISKinematics(), Rivet::DISLepton::DISLepton(), Rivet::EventMixingBase::EventMixingBase(), Rivet::GammaGammaKinematics::GammaGammaKinematics(), Rivet::GammaGammaLeptons::GammaGammaLeptons(), Rivet::GammaGammaLeptons::GammaGammaLeptons(), Rivet::GeneratedCentrality::GeneratedCentrality(), Rivet::HadronicFinalState::HadronicFinalState(), Rivet::HeavyHadrons::HeavyHadrons(), Rivet::Hemispheres::Hemispheres(), Rivet::InvisibleFinalState::InvisibleFinalState(), Rivet::LeadingParticlesFinalState::LeadingParticlesFinalState(), Rivet::LossyFinalState< FILTER >::LossyFinalState(), Rivet::LossyFinalState< FILTER >::LossyFinalState(), Rivet::MC_pPbMinBiasTrigger::MC_pPbMinBiasTrigger(), Rivet::MC_SumETFwdPbCentrality::MC_SumETFwdPbCentrality(), Rivet::ATLAS::MinBiasTrigger::MinBiasTrigger(), Rivet::MissingMomentum::MissingMomentum(), Rivet::NeutralFinalState::NeutralFinalState(), Rivet::NeutralFinalState::NeutralFinalState(), Rivet::NonHadronicFinalState::NonHadronicFinalState(), Rivet::ParisiTensor::ParisiTensor(), Rivet::PercentileProjection::PercentileProjection(), Rivet::PrimaryHadrons::PrimaryHadrons(), Rivet::PrimaryHadrons::PrimaryHadrons(), Rivet::SmearedMET::SmearedMET(), Rivet::SmearedMET::SmearedMET(), Rivet::Spherocity::Spherocity(), Rivet::ATLAS::SumET_PB_Centrality::SumET_PB_Centrality(), Rivet::ATLAS::SumET_PBPB_Centrality::SumET_PBPB_Centrality(), Rivet::TauFinder::TauFinder(), Rivet::TriggerCDFRun0Run1::TriggerCDFRun0Run1(), Rivet::TriggerCDFRun2::TriggerCDFRun2(), Rivet::UndressBeamLeptons::UndressBeamLeptons(), Rivet::ALICE::V0AndTrigger::V0AndTrigger(), Rivet::ALICE::V0Trigger< MODE >::V0Trigger(), Rivet::VetoedFinalState::VetoedFinalState(), Rivet::VisibleFinalState::VisibleFinalState(), Rivet::VisibleFinalState::VisibleFinalState(), Rivet::CentralityProjection::add(), Rivet::CentralityBinner< T, MDist >::setProjection(), and Rivet::VetoedFinalState::vetoFinalState().

◆ declare() [2/2]

template<typename PROJ >
const PROJ & Rivet::ProjectionApplier::declare ( const std::string &  name,
const PROJ &  proj 
) const
inlineprotectedinherited

Register a contained projection (user-facing, arg-reordered version)

Todo:
Add SFINAE to require that PROJ inherit from Projection

◆ get()

template<typename PROJ >
const PROJ & Rivet::ProjectionApplier::get ( const std::string &  name) const
inlineinherited

Get the named projection, specifying return type via a template argument (user-facing alias).

Todo:
Add SFINAE to require that PROJ inherit from Projection

◆ getProjection() [1/2]

template<typename PROJ >
const PROJ & Rivet::ProjectionApplier::getProjection ( const std::string &  name) const
inlineinherited

Get the named projection, specifying return type via a template argument.

Todo:
Add SFINAE to require that PROJ inherit from Projection

References Rivet::ProjectionHandler::getProjection(), and Rivet::ProjectionApplier::getProjHandler().

Referenced by Rivet::CentralityProjection::compare(), Rivet::pcmp(), Rivet::pcmp(), Rivet::pcmp(), and Rivet::pcmp().

◆ getProjection() [2/2]

const Projection & Rivet::ProjectionApplier::getProjection ( const std::string &  name) const
inlineinherited

Get the named projection (non-templated, so returns as a reference to a Projection base class).

References Rivet::ProjectionHandler::getProjection(), and Rivet::ProjectionApplier::getProjHandler().

◆ getProjectionFromDeclQueue()

template<typename PROJ >
const PROJ & Rivet::ProjectionApplier::getProjectionFromDeclQueue ( const std::string  name) const
inlineinherited

Get a named projection from this projection appliers declqueue TODO for TP: Recursion?

References MSG_ERROR.

◆ mkNamedPCmp()

◆ mkPCmp()

Cmp< Projection > Rivet::Projection::mkPCmp ( const Projection otherparent,
const std::string &  pname 
) const
protectedinherited

Shortcut to make a named Cmp<Projection> comparison with the *this object automatically passed as one of the parent projections.

Note
Alias for mkNamedPCmp

Referenced by Rivet::ALICE::PrimaryParticles::compare(), Rivet::SmearedJets::compare(), Rivet::SmearedMET::compare(), Rivet::SmearedParticles::compare(), and Rivet::Correlators::compare().

◆ name()

virtual std::string Rivet::Projection::name ( ) const
inlinevirtualinherited

◆ project()

void Rivet::Thrust::project ( const Event e)
inlineprotectedvirtual

Perform the projection on the Event.

Implements Rivet::Projection.

References calc().

◆ setProjectionHandler()

void Rivet::ProjectionApplier::setProjectionHandler ( ProjectionHandler projectionHandler) const
protectedinherited
Todo:
AB: Add Doxygen comment, follow surrounding coding style

◆ thrust()

double Rivet::Thrust::thrust ( ) const
inline

Thrust scalar accessors The thrust scalar, \( T \), (maximum thrust).

◆ thrustAxis()

const Vector3 & Rivet::Thrust::thrustAxis ( ) const
inline

Thrust axis accessors The thrust axis.

Referenced by axis1().


The documentation for this class was generated from the following file:
  • /Users/chrisg/software/rivet/include/Rivet/Projections/Thrust.hh